From 8151942151fe1cbf072414d8822b80b00abfbf42 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Thu, 28 Jun 2018 13:38:16 +0200 Subject: [PATCH] s390x/kvm: legacy_s390_alloc() only supports one allocation We always allocate at a fixed address, a second allocation can therefore of course never work. We would simply overwrite mappings. This can e.g. happen in s390_memory_init(), if trying to allocate more than > 8TB. Let's just bail out, as there is no need for supporting it (legacy handling for z/VM). Signed-off-by: David Hildenbrand Message-Id: <20180628113817.30814-2-david@redhat.com> Reviewed-by: Christian Borntraeger Signed-off-by: Cornelia Huck --- target/s390x/kvm.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c index 8bcd832123..a9d6d606df 100644 --- a/target/s390x/kvm.c +++ b/target/s390x/kvm.c @@ -752,12 +752,20 @@ int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, uint8_t ar, void *hostbuf, */ static void *legacy_s390_alloc(size_t size, uint64_t *align, bool shared) { - void *mem; + static void *mem; + + if (mem) { + /* we only support one allocation, which is enough for initial ram */ + return NULL; + } mem = mmap((void *) 0x800000000ULL, size, PROT_EXEC|PROT_READ|PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS | MAP_FIXED, -1, 0); - return mem == MAP_FAILED ? NULL : mem; + if (mem == MAP_FAILED) { + mem = NULL; + } + return mem; } static uint8_t const *sw_bp_inst; -- 2.30.2